 /*******************************************************************************
  * Copyright (c) 2007 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  ******************************************************************************/

 package org.eclipse.ui.internal;

 import org.eclipse.core.commands.ExecutionEvent;
 import org.eclipse.core.commands.ExecutionException;
 import org.eclipse.core.expressions.EvaluationResult;
 import org.eclipse.core.expressions.Expression;
 import org.eclipse.core.expressions.ExpressionInfo;
 import org.eclipse.core.expressions.IEvaluationContext;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.ui.IEditorPart;
 import org.eclipse.ui.ISources;
 import org.eclipse.ui.IWorkbenchPage;
 import org.eclipse.ui.IWorkbenchWindow;
 import org.eclipse.ui.handlers.HandlerUtil;

 /**
  * Closes all active editors
  * <p>
  * Replacement for CloseAllAction
  * </p>
  *
  * @since 3.3
  *
  */
 public class CloseAllHandler extends AbstractEvaluationHandler {
     private Expression enabledWhen;

     public CloseAllHandler() {
         registerEnablement();
     }

     public Object execute(ExecutionEvent event) throws ExecutionException {
         IWorkbenchWindow window = HandlerUtil
                 .getActiveWorkbenchWindowChecked(event);
         IWorkbenchPage page = window.getActivePage();
         if (page != null) {
             page.closeAllEditors(true);
         }

         return null;
     }

     /*
      * (non-Javadoc)
      *
      * @see org.eclipse.ui.internal.AbstractEvaluationHandler#getEnabledWhenExpression()
      */
     protected Expression getEnabledWhenExpression() {
         if (enabledWhen == null) {
             enabledWhen = new Expression() {
                 public EvaluationResult evaluate(IEvaluationContext context)
                         throws CoreException {
                     IEditorPart part = InternalHandlerUtil
                             .getActiveEditor(context);
                     if (part != null) {
                         return EvaluationResult.TRUE;

                     }
                     return EvaluationResult.FALSE;
                 }

                 /*
                  * (non-Javadoc)
                  *
                  * @see org.eclipse.core.expressions.Expression#collectExpressionInfo(org.eclipse.core.expressions.ExpressionInfo)
                  */
                 public void collectExpressionInfo(ExpressionInfo info) {
                     info.addVariableNameAccess(ISources.ACTIVE_EDITOR_NAME);
                 }
             };
         }
         return enabledWhen;
     }
 }

